1. Field of the Invention
The present invention relates to a linear anatomic surgical stapling instrument and a surgical staple magazine used therein. More particularly, the invention relates to a gastrointestinal anatomic stapling instrument, which is also known as a gastrointestinal anastomosis instrument or device, for suturing body organs and tissue and to such an instrument that includes components that may be made more easily yet exhibit improved rigidity.
2. Description of the Prior Art
Historically, suturing of a surgical or other wound in organs and tissue has been done by hand. Conventional hand suturing techniques require a high degree of surgical skill. However, expertise in such techniques can vary widely from surgeon to surgeon, thereby resulting in widely varying quality in performance of the concluding steps of an operative procedure. In addition, even very skillful surgeons require a considerable amount of time to suture even relatively small wounds. Therefore, it is possible that an undesirable amount of blood may be lost during the suturing operation.
Accordingly, there has been an increasing tendency in recent years to use surgical staples to suture body organs and tissue after a medical procedure. Surgical staples have been particularly effective in suturing body organs and tissue such as the lung, as well as the esophagus, the stomach, the duodenum, and other body organs in the intestinal tract.
The advent of surgical stapling has provided several marked advantages over known hand suturing techniques. First, since one or more rows of surgical staples are inserted into tissue using a specially adapted instrument that is relatively simple to operate, near uniformity of the closure from one surgeon to the next results. In addition, all staples in the closure are usually inserted simultaneously or in rapid sequence across the entire wound. Therefore, the closure is made very quickly to minimize loss of blood.
The specially adapted instruments for inserting surgical staples are mechanically operated and may be known as anastomosis devices, such as the gastrointestinal anastomosis devices of the type to which this invention relates In such devices, the staples are loaded in one or more elongated rows into a magazine or cartridge. The magazine is then mounted in the device, which includes a mechanism for pushing, or driving, the staples from the magazine through two or more sections of tissue toward a deforming anvil. At the conclusion of the driving operation, the legs of each staple are clamped or bent, by engagement with the anvil, to a closed configuration to complete the suture and join the tissue sections together.
Known gastrointestinal anastomosis stapling instruments usually include a pair of elongated jaws that are maneuvered to position the tissue to be sutured therebetween. The jaws are then clamped tightly together. One of the jaws supports the staple magazine with at least two laterally spaced rows of staples and cooperating staple drivers, and the other jaw supports an anvil with similar complementary rows of staple-forming pockets, each pair of which is aligned with one staple in the cartridge. A reciprocal slide is mounted with one jaw and when advanced therealong longitudinally actuates staple-driving cam surfaces to sequentially depress the staple drivers and drive the staples through the body tissue toward the anvil. Additionally, a knife blade may be advanced with the cam surfaces to slice the tissue between the two rows of deformed staples immediately following the staple deformation so that the adjacent sutured tissue sections can be separated.
As may thus be expected, linear stapling instruments provide many benefits, such as those described above. However, they also have certain drawbacks. For one, many known instruments include a lower jaw made of heavy gauge metal formed into a channel having a C-shaped cross-section with the back of that cross-section at the bottom of the device and the legs bent upwardly and then inwardly toward each other to define a narrow, upwardly facing slot. Staple deforming pockets are then formed in the upwardly facing surfaces of the legs on either side of the slot, thereby to define the anvil. Immediately after staples are driven toward the pockets, the cutting blade may be advanced through the slot to slice tissue that has been sutured with the staples on either side. However, this known lower jaw configuration is difficult to manufacture. Moreover, under high tissue clamping forces between the jaws, the lower jaw is subject to twisting and bending so that the staple-deforming pockets in the anvil may become misaligned with staples in the magazine. Therefore, sutures may not be reliably formed.
Accordingly, further advances and improvements in linear surgical stapling instruments are needed.